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Simulations
Bundled Simulations

Bundled Simulations

Simulation Bundles enable you to simulate several transactions consecutively. For example, to set a particular conditions before simulating a desired transaction, you first need to execute several other transactions.

Both Simulation API and Simulation RPC support bundled simulations. The endpoints receive an array of transactions that get simulated one after another within the same block.

RPC bundled simulations

Node RPC allows you to read blockchain data and send transactions. But you can also simulate bundled transactions on the Node through a single RPC URL. Simulations via RPC are only available on supported networks. If your network is not supported on Node, run bundled simulations via Simulation API instead.

Retrieve the RPC URL from the Dashboard.

Go to Node > Copy HTTPS URL of the desired network.

example
https://mainnet.gateway.tenderly.co/$TENDERLY_NODE_ACCESS_KEY

To simulate bundled transactions via RPC, call the tenderly_simulateBundle method. This custom method allows you to simulate several transactions by passing them as an array. See RPC reference.

Transactions are simulated one after the other in the same block.

Example

example
curl https://mainnet.gateway.tenderly.co/$TENDERLY_NODE_ACCESS_KEY \
  -X POST \
  -H "Content-Type: application/json" \
  -d \
  '{
    "id": 0,
    "jsonrpc": "2.0",
    "method": "tenderly_simulateBundle",
    "params": [
      [
        {
          "from": "0xe2e2e2e2e2e2e2e2e2e2e2e2e2e2e2e2e2e2e2e2",
          "to": "0x6b175474e89094c44da98b954eedeac495271d0f",
          "data": "0x40c10f19000000000000000000000000e58b9ee93700a616b50509c8292977fa7a0f8ce10000000000000000000000000000000000000000000000001bc16d674ec80000"
        },
        {
          "from": "0xe58b9ee93700a616b50509c8292977fa7a0f8ce1",
          "to": "0x6b175474e89094c44da98b954eedeac495271d0f",
          "gas": "0x7a1200",
          "data": "0x095ea7b3000000000000000000000000f7ddedc66b1d482e5c38e4730b3357d32411e5dd0000000000000000000000000000000000000000000000000de0b6b3a7640000"
        },
        {
          "from": "0xf7ddedc66b1d482e5c38e4730b3357d32411e5dd",
          "to": "0x6b175474e89094c44da98b954eedeac495271d0f",
          "gas": "0x7a1200",
          "data": "0x23b872dd000000000000000000000000e58b9ee93700a616b50509c8292977fa7a0f8ce1000000000000000000000000bd8daa414fda8a8a129f7035e7496759c5af8570000000000000000000000000000000000000000000000000006a94d74f430000"
        }
      ],
      "latest",
      {
        "0x6b175474e89094c44da98b954eedeac495271d0f": {
          "stateDiff": {
            "0xedd7d04419e9c48ceb6055956cbb4e2091ae310313a4d1fa7cbcfe7561616e03": "0x0000000000000000000000000000000000000000000000000000000000000001"
          }
        }
      }
    ]
  }'

API bundled simulations

Use the simulate-bundle API endpoint to simulate multiple consecutive transactions at once. See API reference.

example
https://api.tenderly.co/api/v1/account/${TENDERLY_ACCOUNT_SLUG}/project/${TENDERLY_PROJECT_SLUG}/simulate-bundle

The simulation output shows the emitted events and state changes the transaction might cause if you send it to the blockchain.

In case a transaction fails, there will be an early return with all simulations up until the failure point.

Example

curl --request POST \
  --url https://api.tenderly.co/api/v1/account/me/project/project/simulate-bundle \
  --header 'Accept: application/json' \
  --header 'Content-Type: application/json' \
  --header "X-Access-Key: $TENDERLY_ACCESS_KEY" \
  --data '{
  "simulations": [
    {
      "network_id": "1",
      "save": true,
      "save_if_fails": true,
      "simulation_type": "full",
      "from": "0xe2e2e2e2e2e2e2e2e2e2e2e2e2e2e2e2e2e2e2e2",
      "to": "0x6b175474e89094c44da98b954eedeac495271d0f",
      "input": "0x40c10f19000000000000000000000000e58b9ee93700a616b50509c8292977fa7a0f8ce10000000000000000000000000000000000000000000000001bc16d674ec80000",
      "state_objects": {
        "0x6b175474e89094c44da98b954eedeac495271d0f": {
          "storage": {
            "0xedd7d04419e9c48ceb6055956cbb4e2091ae310313a4d1fa7cbcfe7561616e03": "0x0000000000000000000000000000000000000000000000000000000000000001"
          }
        }
      }
    },
    {
      "network_id": "1",
      "save": true,
      "save_if_fails": true,
      "simulation_type": "full",
      "from": "0xe58b9ee93700a616b50509c8292977fa7a0f8ce1",
      "to": "0x6b175474e89094c44da98b954eedeac495271d0f",
      "input": "0x095ea7b3000000000000000000000000f7ddedc66b1d482e5c38e4730b3357d32411e5dd0000000000000000000000000000000000000000000000000de0b6b3a7640000"
    },
    {
      "network_id": "1",
      "save": true,
      "save_if_fails": true,
      "simulation_type": "full",
      "from": "0xf7ddedc66b1d482e5c38e4730b3357d32411e5dd",
      "to": "0x6b175474e89094c44da98b954eedeac495271d0f",
      "input": "0x23b872dd000000000000000000000000e58b9ee93700a616b50509c8292977fa7a0f8ce1000000000000000000000000bd8daa414fda8a8a129f7035e7496759c5af8570000000000000000000000000000000000000000000000000006a94d74f430000"
    }
  ]
}'

Explore use cases

Where to go next

Single simulations
Simulate via SDK
Single SimulationsTransaction Preview